This invention relates to semiconductor memories and more particularly to improvements therein.
In semiconductor memories of the type having an array of elements each of which effectively constitutes a flip flop for binary data storage, it is customary to use two sense lines for say, each column of elements in the array. When a row of elements in an array is accessed for read out, one of the sense lines for each element is high and the other is low, indicative of the information stored in each element. When another row of elements is accessed for read out, the same sense lines as were used for the previous access row are excited again in response to the information contained in the latest access row.
It can happen that if insufficient time is allowed to permit the sense lines to recover from a previous read out, they do not settle back to their quiescent state. The voltage levels which the nonrecovered sense lines have at the time of a second read out may be such as to cause the memory to lose the data that is stored therein. That is, the voltage level on the nonrecovered sense lines acts to change the data stored in the memory.
It will be apparent that the need for time for the memory to "settle down" after a read out operation reduces the speed at which the memory can be operated.